An improved fastener is received in a member and held against axial and rotational movement relative to the member by an interaction between the member and the fastener.
A fastener which is held against axial and rotational movement relative to a sheet metal member by an interaction between the member and the fastener is disclosed in U.S. Pat. No. 4,389,766. The fastener disclosed in this patent has a shank section which extends axially outwardly from a head section and has a central axis which is coincident with the central axis of the head section. The shank section and rim of this fastener have side surfaces which cooperate to define a generally annular groove.
The side surfaces of the groove have a common center of curvature. Therefore, the distance between the side surfaces of the groove remains constant in a circumferential direction around the shank of the fastener. Since the distance between the side surfaces remains constant, the side surfaces cannot cooperate to resist relative rotation between the fastener and a sheet metal member.
The fastener of U.S. Pat. No. 4,389,766 is provided with relatively deep circular indentations in the rim of the fastener. Due to depth of the circular indentations, the sheet metal does not flow smoothly into the indentations in the rim of the fastener. Therefore, wrinkles tend to form in the sheet metal where the sheet metal goes into the indentations in the rim of the fastener.